That's what I was thinking. I saw some vids on youtube talking about how the leghorn hens have been bred in to the egg machines we have today. Wish I could remember which video it was, but anyway, they were saying something to the affect that leghorns from 40-50 years ago layed about 100 eggs per year. Now, the production egg layers are pushing 300+/- per year.
I was talking to one of my co-workers today about chickens and eggs and all that. When he found out the chicken in the market grows to butcher weight in 6-8 weeks I thought he was gonna have a heart attack. Within another 1/2 hour of the conversation, he was asking where to buy chickens to raise his own.